Oxazinoindole- and thiazinoindole derivatives

ABSTRACT

Oxazinoindole derivatives characterized by having an amino(lower)alkyl radical attached to the 1 position of a 1H-1,4oxazino(4,3-a)indole nucleus are disclosed. The amino portion of the amino(lower)alkyl radical may be further substituted with one or two lower alkyl groups or incorporated in a heterocyclic amino radical. The derivatives are substituted further at positions 1 and 10 and may be optionally substituted at positions 3, 4, 6, 7, 8 and 9. The oxazinoindole derivatives of this invention are useful antidepressant and antiulcer agents. Methods for the preparation and use of these derivatives are also disclosed.

United States Patent [191 Demerson et al.

[451 Oct. 7, 1975 I OXAZINOINDOLE- AND THIAZINOINDOLE DERIVATIVES [75] Inventors: Christopher A. Demerson; Leslie G. Humber; George Santroch; Thomas A. Dohson; Ivo Jirkovsky, all of Montreal, Canada [73] Assignee: Ayerst, McKenna and Harrison Ltd., Montreal, Canada [22] Filed: ,Iune I9, 1974 [21] Appl, No.: 480,998

Related US. Application Data [62] Division of Ser. No. 226,287, Feb. 14, 1974, Pat. No.

[52] US. Cl 260/243 R; 260/244 R; 424/246;

424/248 [51] Int. Cl. C07D 279/14; C07D 265/28 [58] Field of Search 260/243 R, 244 R [56] References Cited UNITED STATES PATENTS 3,532,719 10/1970 Theimer 260/3452 3,833,575 9/1974 Demerson et al 260/243 FOREIGN PATENTS OR APPLICATIONS 2,05 l ,496 4/1971 Germany OTHER PUBLICATIONS Rieche et al., Synthetic Methods of Organic Chemistry," Vol. [2, p. 361, S. Karger, New York (1958).

Warren et al., Synthetic Methods of Organic Chemistry," Vol. 13, pp. 361-362, S. Karger, New York (1959).

Primary Examiner-lohn M. Ford Attorney, Agent, or Firm-John P. Floyd [5 7] ABSTRACT 20 Claims, N0 Drawings OXAZINOINDOLE- AND Tl-IIAZINOINDOLE DERIVATIVES This is a division of application Ser. No. 226,287, filed Feb. 14, I974.

BACKGROUND OF THE INVENTION l. Field of Invention This invention relates to novel oxazinoindole and thiazinoindole derivatives, to processes for their preparation and to intermediates used in these processes. For convenience, further reference in this specification will be made to these compounds as oxazinoindole derivatives.

More specifically, the present invention relates to oxazinoindole derivatives possessing valuable pharmacologic properties. For example, these derivatives exhibit useful antidepressant properties at dosages which do not elicit undesirable side effects. Furthermore the present derivatives exhibit properties useful for the treatment and prevention of ulcers. The combination of these pharmacologic properties together with a low order ot toxicity render the oxazinoindoles of the invention therapeutically useful.

2. Description of the Prior Art Very little attention has been given to L4- oxazino[4,3-a]indole derivatives prior to this disclosure. In the few reports that do exist, such as the reports, by .I. A. Elvridge and F. S. Spring, 1. Chem. Soc., 2935 (1949) and W. R. Smith and R. Y. Moir, Can. J. Chem., 30, 4l 1 (I952), the oxazinoindole derivatives are treated more in the manner of chemical curiosities. In these instances. the oxazinoindoles are distinguished readily from the compounds of this invention by having the pyran portion of their ring system at a higher oxidation state.

SUMMARY OF THE INVENTION The oxazinoindole derivatives of this invention are characterized by having an amino(lower)alkyl radical attached to a lH- l ,4-oxazino{4,3-a]indole nucleus. The preferred derivatives of this invention are represented by formula I.

in which R is lower alkyl or lower cycloalkyl; R R, R and R are the same or different selected from the group consisting of hydrogen or lower alkyl; R" is hydrogen, lower alkyl, hydroxy, lower alkoxy, lower alkanoyloxy, nitro or halo, R is lower alkyl; X is oxy or thio; and Alk-NR'R is an amino(lower)alkyl radical in which Alk is an alkylene selected from the group consisting of CR"R", CR'"R"CR R", CRIURIICRI2R|3RI4RI5 d CRIURIICRIZRIIICRI4RI5CRI6RI7 i Rlll RH, R121 R, R, R, R'" and R are hydrogen or lower alkyl, and R" and R are either the same or different selected from the group consisting of hydrogen and lower alkyl, or R and R together with the nitrogen atom to which they are joined form a heterocyclic amine radical selected from the group consisting of l-pyrrolidinyl, piperidino, morpholino, piperazino, 4-(lower alkyl)-lpiperazinyl and 4-[ hydroxy( lower)alkyl l -piperazinyl.

DETAILED DESCRIPTION OF THE INVENTION The term lower alkyl" as used herein contemplates straight chain alkyl radicals containing from one to six carbon atoms and branched chain alkyl radical containing up to four carbon atoms and includes methyl, ethyl, propyl, isopropyl, butyl, isobutyl, 2-methylpentyl and the like.

The term lower cycloalkyl as used herein contemplates saturated cyclic hydrocarbon radicals containing from three to six carbon atoms and includes cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl.

The term lower alkoxy" as used herein contemplates both straight and branched chain alkoxy radicals containing from one to four carbon atoms and includes methoxy, ethoxy, isopropoxy, t-butoxy and the like.

The term lower alkanoyloxy as used herein contemplates both straight and branched chain alkanoyloxy radicals containing from two to six carbon atoms and includes acetoxy, propionyloxy, pivaloyloxy, hexanoyloxy and the like.

The term halo" as used herein contemplates halogens and includes fluorine, chlorine, bromine and iodine.

The compounds of formula I are capable of forming acid addition salts with pharmaceutically acceptable acids. Such acid addition salts are included within the scope of this invention.

The acid addition salts are prepared by reacting the base form of the appropriate compound of formula I with either one or two equivalents, depending on the number of basic nitrogens in the compound, or preferably with an excess of the appropriate acid in an organic solvent, for example, ether or an ethanol-ether mixture. These salts, when administered to mammals, possess the same pharmacologic activities as the corresponding bases. For many purposes it is preferable to administer the salts rather than the base compounds. Among the acid addition salts suitable for this purpose are salts such as the sulfate, phosphate, lactate, tartrate, maleate, citrate, hydrobromide and hydrochloride. Both the base compounds and the salts have the distinct advantage of possessing a relatively low order of toxicity.

Also included in this invention are the stereochemical isomers of the compounds of formula I which result from asymmetric centers, contained therein. These isomeric forms may be prepared by different methods and are purified readily by crystallization or chromatography.

Individual optical isomers, which might be separated by fractional crystallization of the diastereoisomeric salts formed thereof, for instance, with dor I- tartaric acid or D-(+)-a-bromocamphor sulfonic acid, are also included.

Antidepressant Activity The useful antidepressant activity of the compounds of formula I and their acid addition salts with pharmaceutically acceptable acids may be demonstrated in standard pharmacologic tests, such for example. the tests described by F. l-Iafliger and V. Burckhart in Psychopharmacological Agents", M. Gordon. Ed., Academic Press, New York and London, l964,pp. 83.

More specifically, as noted in the latter reference the antidepressant properties of a compound may be demonstrated by its capacity to antagonize the depressant effects of reserpine. Furthermore, it is well documented that reserpine in animals products a model depression which can be used for detecting antidepressant properties. Accordingly, the compounds of the present invention antagonize reserpine effects in mice at doses ranging from about I to I mg/kg. Several of the preferred compounds, for instance.

I l O-dimethyll 2-(ethylamino )ethyl ]-3,4-dihydrolH-l ,4-oxazino[4,3-a]indole hydrobromide (Example 284), l,l0-dimethyll -[(2-dimethylamino )ethyl ]-3,4- dihydrol H-l ,4-oxazino[4,3-a]indole hydrochloride (Example 284), l-( 3-aminopropyl l l0-dimethyl-3,4-dihydrol H- l ,4- oxazino-[4,3-a]indole hydrochloride (Example 286), l, l O-dimethyll 3-( methylamino )propyl ]-3,4- dihydro-l H-l ,4-oxazino[4,3-a]indole hydrochloride (Example 285) and l,l0-dimethyll 3-( dimethylamino )propyl]-3,4-

dihydro- H- l ,4-oxazino[4,3-a]indole hydrochloride (Example 287), antagonize the effects of reserpine in mice at dose ranges from about I to mg/kg.

When the compounds of this invention are used as antidepressants in warm-blooded mammals, e.g. rats and mice, they may be used alone or in combination with pharmacologically acceptable carriers, the proportion of which is determined by the solubility and chemical nature of the compound, chosen route of administration and standard biological practice. For example, they may be administered orally in solid form containing such excipients as starch, milk sugar, certain types of clay and so forth. They may also be administered orally in the form of solutions of they may be injected parenterally. For parenteral administration they may be used in the form ofa sterile solution containing other solutes, for example, enough saline or glucose to make the solution isotonic.

The dosage of the present therapeutic agents will vary with the form of administration and the particular compound chosen. Furthermore, it will vary with the particular host under treatment. Generally, treatment is initiated with small dosages substantially less than the optimum dose of the compound. Thereafter, the dosage is increased by small increments until the optimum effect under the circumstances is reached. In general, the compounds of this invention are most desirably administered at a concentration level that will generally afford effective results without causing any harmful or deleterious side effects and preferably at a level that is in a range of from about 0.1 mg to about 50 mg per kilo per day, although as aforementioned variations will oc cur. However, a dosage level that is in the range of from about 0.5 mg to about 25 mg per kilo per day is most desirably employed in order to achieve effective results.

Antiulcer Acticity The compounds of formula I of this invention possess another useful pharmacologic property; that is, they are useful antiulcer agents. More particularly, the said compounds of this invention exhibit antiulcer activity in standard pharmacologic tests, for example, the test described by D. A. Brodie and L. S. Valitski, Proc. Soc.

Exptl. Biol. Med, l 13, 998 (1963), based on the prevention of stress-induced ulcers.

When the compounds of formula I are employed as antiulcer agents, they may be formulated and administered in the same manner as described above for their use as antidepressant agents.

Processes For the preparation of the oxazinoindoles of this invention we prefer to use as starting materials the compounds of formula II,

in which R and R are as defined in the first instance.

The starting materials of formula ll are either well known, for example, skatole and 3-ethylindole, or they may be prepared from indole or known indole derivatives, for example, see P. L. Julian, et al., Heterocyclic Compounds", R. C. Elderfield, Ed., Vol. 3, John Wiley and Sons, lnc., New York, 1952, p. 1, according to the method of R. Robinson, et al., described in US. Pat. No. 2,407,452, issued Sept. 10, 1946.

The starting material of formula ll is then converted to the key intermediate of formula III,

I an

in which R R, R R R' and R are as defined in the first instance and X is hydroxy or mercapto.

This conversion may be effected by several methods. One general method involves reacting the appropriate lithium derivative of the starting material of formula ll with ethylene oxide or an appropriate lower alkyl substituted ethylene oxide to afford the desired intermediate of formula III in which X is hydroxy. The desired intermediates may also be obtained by treating the appropriate starting material of formula ll with the appropriate ethylene oxide derivative according to the procedure of M. Julia, et al., Bull. Soc. Chim. Fr., 229l 1966).

The lower alkyl substituted ethylene oxides are pre pared by known methods; for example, see V. Franzen and H. E. Driesen, Chem. Ber., 96, 1881 (1963).

An alternative method for the preparation of intermediates of formula III in which R and R are hydrogen involves treating the starting material of formula [I with an a-haloacetic acid lower alkyl ester of formula LCR*R"COO (lower alkyl) in which L is halo and R and R are as defined in the first instance, in the presence of a suitable proton acceptor and using preferably an inert solvent for the reaction. The a-haloaeetic acid lower alkyl esters are well known, for example see Rodds Chemistry of the Carbon Compounds", S. Coffey, Ed., Vol. lc, 2nd ed., Elsevier Puboishing Co., Amsterdam, 1965, pp. 201 205. Suitable proton acceptors include sodium hydride, alkali metal carbonates and triethylamine. Suitable inert solvents include tetrahydrofuran, benzene, toluene and dimethylformamide. Preferred conditions for the N-alkylation include the use of sodium hydride as a proton acceptor and tetrahydrofuran as an inert solvent. Although the optimum temperature and reaction time will vary depending on the reactants employed, the reaction is gen erally performed at the boiling point of the reaction mixture for a period of 30 minutes to 48 hours.

The indole-l-acetic acid lower alkyl ester derivative obtained by the above N-alkylation reaction is thereafter hydrolyzed, preferably with a solution of potassium hydroxide in methanol water, to give the corresponding indole-l-aeetic acid derivatives which on reduction with lithium aluminum hydride afi'ords the desired intermediate of formula ill in which R'- and R are hydrogen and X is hydroxy.

Again alternatively, the latter indole-l-acetic acid derivative may also be reacted with two equivalents of a lower alkyl Grignard reagent, for example, methyl magnesium bromide, to give, after hydrolysis of the magnesium-halogen derivative, the desired intermediates of formula III (R =R"= lower alkyl and X, hy droxy), see L. F. Ficser and M. Fieser, Advanced Organic Chemistry", Reinhold Publishing Corp., New York, 196i, p. 272.

When the corresponding intermediates of formula III in which X is mercapto are desired, a procedure similar to that described by N. N. Suvorov and V. N. Buyanov, Khim.-Farm. ZH., l, (1967), [Chem Abstr. 67. 73474a l967)], for converting 3-(2-bromoethyl)- indole to indole-3-ethanethiol, may be employed. More particularly, the above intermediate of formula ill in which X is hydroxy is treated with phosphorus tribromide in an inert solvent, for example, ether or carbon tetrachloride, followed by treatment of the product with sodium or potassium thiosulfate to afford the corresponding sodium or potassium B-( l-indolyl)ethyl thiosulfate derivative, respectively. Treatment of the latter product with strong alkali, for example, sodium or potassium hydroxide, yields the corresponding bis- [w-(indolyl)ethyl]disulfide derivative. Finally reduction of the latter compound with lithium aluminum hydride gives the desired intermediate of formula III in which X is mercapto.

Alternatively, the starting materials of formula III in which R and R are hydrogen and X is mercapto may be prepared by oxidizing the corresponding intermediate of formula III in which X is hydroxy, described above, with N,N-dicyclohexylcarbodiimide and dimethyl sulfoxide in the presence of a suitable acid, for example, trifluoroacetic acid, see K. E. Pfitzner and J. G. Moffat, J. Amer. Chem. Soc, 87, 5670 (I965), to give the corresponding aldehyde derivative. The same aldehyde derivative may also be obtained by N- alkylation of the appropriate starting material of formula ll with an appropriate a-halo-acetaldehyde derivative (see Rodds Chemistry of the Carbon Compounds", cited above, Vol., lc, pp. 24 26) according to the conditions described above for N-alkylation with a-haloacetic acid lower alkyl esters.

The latter aldehyde derivative is converted to its corresponding gem-dithiol derivative with hydrogen sulfide, which is reduced with lithium aluminum hydride, according to the method ofT, l... Cairns, et al., J. Amer. Chem. Soc., 74, 3982 I952), to yield the desired starting material of formula III.

It should be noted that the preceding processes may not be entirely practical for the prepparation of the compounds of formula Ill in which X is hydroxy or mercapto and R is hydroxy or lower alkanoyloxy. For

this reason, the preferred starting materials of formula ll for the ultimate preparation of the compounds of formula l in which R is hydroxy or lower alkanoyloxy are the corresponding compounds of formula II in which R is benzyloxy, ie a hydroxyl with a protecting benzyl group or other suitable protecting group (see J. F. W. McOmie, Advances in Organic Chemistry, Vol. 3, R. A. Raphael, et 21]., Ed., lnterscience Publishers, New York, i963, pp. 191 294). After the appropriate transformations described below, the benzyloxy group is removed by hydrogenation, in the presence of a catalyst, for example, 10% palladium on carbon, just prior to affording the desired corresponding compound of formula 1 in which R is hydroxy. The latter may be converted if desired to the corresponding compound of formula I in which R is lower alkanoyloxy by conventional means, for example, by treatment with the appropriate lower alkanoic anhydride preferably in the presence of pyridine.

The above described intermediate of formula III in which R, R R R R", R and X are as defined in the first instance are now subjected to a key reaction comprising the treatment of said starting materials with a compound of formula in which R is as defined in the first instance and Z is selected from the group consisting of:

a. COOR and Alk COOR" in which R is hydrogen or lower alkyl and Alk is an alkylcne selected from the group consisting of CRR, CRIURIICRIZRl-i d CRIURIICRIZRIISCRLiRlS wherein R", R, R, R, Rand R are hydrogen or lower alkyl,

b. CONRR and Alk-CONRR in which Alk, R

and R are as defined above,

c. CH OCOR and All' Cl-l OCOR in which R is hydrogen or lower alkyl and Alk is as defined above,

d. Alk L in which Alk is an alkylene selected from the group consisting of CRRCHR CRRCR RCHR and CR"RCR"R CRR 'CHR" wherein R, R, R R, R, R and R are as defined above and L is halo,

c. Alk NRCOR in which Alk and R are as defined in the first instance and R is hydrogen or lower alkyl containing from one to five carbon atoms, and

f. Alk-N0 in which Alk is as defined in the first instance, in the presence of an acid catalyst to yield the compounds of formula V in which R, R R R R R, R, X and Z are as defined above.

7 o LQ 1 .8.;

n a In tin a cx n x Thereafter the appropriate compound of formula V is convened to the desired oxazincindole of formula 1 according to the processes described hereinafter.

In practising the condensation (lll Vl V) we have found it preferable to use a solvent as a reaction medium. Any solvent inert to the reaction conditions may be used. Suitable solvents include aromatic hydrocarbons, for example, benzene or toluene, ethers and cyclic ethers, for example, diethyl ether, dioxan or tetrahydrofuran, halogenated hydrocarbons, for example methylene dichloride or carbon tetrachloride and the like. Benzene and toluene are especially convenient and practical for this use. A variety of suitable acid catalysts may be used for this condensation, for example, the type of catalyst used in a Friedel-Crafts Reaction, i.e. p-toluenesulfonic acid, aluminum chloride, phosphorus pentoxide, boron trifluoride, zinc chloride, hydrochloric acid, perchloric acid, trifluoroacetic acid, sulfuric acid and the like. p-Toluenesulfonic acid, aluminum chloride, boron trifluoride and phosphorus pentoxide are included among the preferred acid catalysts. The amount of acid catalyst used is not especially critical and may range from 0.01 molar equivalents to I00 molar equivalents; however, a range of from 0.1 to ID molar equivalents is generally preferred. The time of the reaction may range from minutes to 60 hours, with the preferred range being from one-half to 24 hours. The temperature of the reaction may range from C. to the boiling point of the reaction mixture. Preferred temperature ranges include 20 to l20C.

A more detailed description of the preparation of the above intermediate compounds of formula V and a description of their subsequent conversion to the oxazinoindole derivatives of formula I are disclosed below. For convenience these descriptions are catagorized into sections according to the group selected for Z for the intermediate.

a. Preparation and Conversion of Intermediates of Formula V (Z COOR'" and Alk-COOR) Intermediates of formula V (Z COOR and Alk COOR in which R is hydrogen or lower alkyl and Alk is as defined in the first instance and R, R, R, R, R R, R and X are as defined in the first instance) are readily obtained by the condensation (Ill IV V) by using ketoacid or ketoesters of formula in which R is as defined in the first instance and Z is COOR" or Alk COOR" as defined above together with the intermediate of formula III.

Generally comparable yields of product are obtained in this process when either the ketoacid or the corresponding ketoester is used. However, in the case where it is desired to prepare an acid compound of formula V in which Z is ALK'COOR' wherein Alk is CR R" and R" is hydrogen (i.e., an acid intermediate of formula V), it is preferable to first condense the appropriate B-ketoester of formula IV rather than the corresponding B-ketoacid and then hydrolyze the resulting ester product to give the desired acid compound.

Moreover, in the general practice of this invention it is often more convenient to prepare the acid compounds of formula V by using the ketoester instead of the ketoacid in this process and then hydrolyze the resulting ester product to the desired acid, the reason being simply that the ketoesters are generally more readily available either commercially or by synthesis.

Compounds of formula V in which 2 is COOR or Alk'COOR' wherein Alk is as defined in the first instance and R" is lower alkyl, i.e. ester intermediates of formula V, are hydrolyzed readily to their corresponding acids of formula V by treatment with a suitable alkali, for example, potassium hydroxide or sodium. carbonate, in aqueous methanol or aqueous ethanol or be treatment with lithium iodide in a suitable organic solvent, for example, collidine, see L. F. Fieser and M. Fieser, Reagents for Organic Synthesis", John Wiley and Sons, Inc, New York, l967, pp. 6l5 617.

The a-, 3-, 7-, and fl-ketoacids and ketoesters of formula lll are either known, for example, ethyl pyruvate, levulinic acid, ethyl a,a-dimethylacetoacetate and Bfi-dimethyllevulic acid or they may be prepared by known methods described in general organic chemistry textbooks. For example, a comprehensive review on the properties and preparation of such 01-, 3-, 7- and 8-ketoacids and -ketoesters may be found in "Rodds Chemistry of the Carbon Compounds", cited above, Vol. Id, pp. 226 274.

Thereafter these intermediate acids and esters of formula V are converted to compounds of formula I in which R, R, R, R, R R", R and X are as defined in the first instance and -Alk-NR"R is an amino(lower)alkyl in which Alk is CH; or AlkCH wherein Alk is as defined in the first instance and R" and R are as defined in the first instance.

ln the case where the acid intermediate of formula V is employed, said acid is subjected to admidation by treatment with a lower alkyl chloroformate, preferably ethyl chloroformate, in the presence of triethylamine, affording the corresponding mixed anhydride, which is converted by treatment with the appropriate amine of formula HNRR in which R" and R are as defined in the first instance, for example, ammonia, methylamine or dimethylamine, to yield the corresponding amide of formula V in which Z is CONRR or AIKCONR R wherein Alk', R" and R are as described in the first instance.

Alternatively, the latter amides are also obtained by treating the ester intermediates of formula V, described above, with the appropriate amine according to known amidation methods, for example, see A. L. F. Beckwith in The Chemistry of Amides, J. Zalicky, Ed., Interscience Publishers, New York, I970, pp. 96 105.

Thereafter, the amides so obtained are reduced with a suitable complex metal hydride to yield the desired oxazinoindoles. Examples of suitable complex metal hydrides are lithium aluminum hydride, lithium aluminum hydride-aluminum chloride, aluminum hydridealuminum chloride, diborane and sodium borohydridealuminum chloride. Lithium aluminum hydride is preferred.

Two aspects of this latter reduction of the amides are worth noting. The first aspect relates to the reduction of the above amides of formula V in which Z is CONRR r Alk'-CONR"R" wherein Alk is as defined in the first instance, R" is hydrogen and R is lower alkyl, i.e. secondary amides, to their corresponding oxazinoindoles of formula I, i.e. secondary amines. In this case a modification of the above process in the following manner is among the preferred procedures. The aforementioned acid or ester intermediate of formula V is reacted with an amine of formula NHRR" in which R" is benzyl and R is lower alkyl corresponding to the R of the desired amine. This step is performed according to the amidation step described above. The resulting amide is then reduced with a complex metal hydride according to the above procedures. Thereafter the benzyl group is removed by hydrogenolysis in the presence of a catalyst, preferably palladium on carbon, to afford the desired secondary amine compounds of formula I.

The second aspect relates to a more general modification for the reduction of the above amides of formula V in which Z is CONR"R or AIk'CONR"R wherein Alk, R. and R is as defined in the first instance.

This modification is applicable to the reduction of the tertiary, secondary and primary amides and is a preferred modification for the reduction of the latter two. In practising this modification, the aforementioned amide of formula V is treated with triethyloxonium fluoroborate, see R. F. Borch. Tetrahedron Letters, No. l, 6] 1968 or dimethyl sulfate, see H. Bredereck, et al., Chem. Ber., 98, 2754 (1965), in an inert solvent, for example, methylene dichloride, whereby the corresponding iminoether fluoroborate or methyl sulfate salt is obtained, respectively. Subsequent reduction of the salt thus obtained with a complex metal hydride according to the procedure described above for reducing amides yields the desired oxazinoindole of formula l. Alternatively, the above fluoroborate or methyl sulfate salt derived from a secondary or primary amide may be decomposed by base treatment, for example, with I07: sodium hydroxide solution or triethylamine, to give the corresponding iminoether derivative which is then reduced in a like manner to the desired oxazinoindole.

When applying the aforementioned steps in the preparation of compounds of formula I in which R is hydroxy or lower alkanoyloxy, it is preferable to use corresponding intermediates in which R is benzyloxy followed by the appropriate transformations as noted previously to yield the desired compounds of formula I.

b. Preparation and Conversion of Intermediates of Formula V (Z CONR"R and Alk'-CONRR).

The intermediates of formula V in which Z is CONR"R and Alk'CONR"R wherein R", R and Alk are as defined in the first instance, described in the previous section, are also obtained directly by utilizing the appropriate starting materials of formula III and 01-, 3-, 'y-, or S-ketoamides of formula in which R is as defined above and Z is CONRR or AlkCOl JR"R in which Alk, R and R are as defined above. The ketoamides required for this condensation are either known, for example, pyruvamide or 0:,a-dimethylacetoacetamide, or they may be prepared by known methods, for instance, see "Rodds Chemistry of the Carbon Compounds", cited above, Vol. ld, pp. 226 274.

Thereafter these amides of formula V are converted by the reduction process, described above, to the compounds of formula I in which R, R R R, R R, R and X are as defined in the first instance and Alk- NR"R is amino(l0wer)alkyl in which Alk is Cl-l or Alk---CH wherein Alk is as defined in the first instance and R" and R are as defined in the first instance.

c. Preparation and Conversion of Intermediates of Formula V (Z CH OCOR and Alk'CH OCOR) Intermediates of formula V in which 2 is CH,. COR and Alk'CH OCOR" in which Alk and R are as defined in the first instance, are obtained when a starting material of formula lll is condensed with a ketoalcohol lower alkanoic acid ester of formula R'COCH OCOR or RCOAlkCH OCOR' in which R, Alk and R are as defined in the first instance in the presence of a suitable acid catalyst according to the conditions described above for the condensation (Ill IV V). The ketoalcohol lower alkyl esters are either known, for example, acetonyl acetate or 5-acetoxy-pentan-2-one, or may be prepared by known methods, for instance, see Rodds Chemistry of the Carbon Compounds", cited above Vol. ld, pp. 49 54.

These intermediates of formula V may then be utilized for the preparation of compounds of formula I of this invention in the following manner. The intermediate is hydrolyzed with an aqueous alcoholic solution of a suitable alkali, for example, sodium hydroxide in aqueous methanol to afford the corresponding primary alcohol. It should be noted that the latter primary alcohols may also be obtained by the direct reduction of the intermediate acids and esters of formula V, described herein in section (a), using a suitable complex metal hydride as described therein. The primary alcohol is then oxidized to the corresponding aldehyde. Although a variety of methods are known for the oxidation of a primary alcohol to its corresponding aldehyde, see for example, Rodds Chemistry of the Carbon Compounds", cited above, Vol. lc, pp. 4 l0, we have found that the method of K. E. Pfitzner and J. G. Moffat, J. Am. Chem. Soc., 87, 5670 (I965), using N,N-dicyclohexylcarbodiimide and dimethyl sulfoxide in the presence of a suitable acid, for example, trifluoroacetic acid, is both efficacious and convenient. Thereafter the aldehyde is reacted with an amine of formula HNRR" in which R and R are as defined in the first instance according to the method of K. N. Campbell, et al., J. Amer. Chem. Soc., 70, 3868 (1948) in the case when the amine used is ammonia or a primary amine, or according to the method of N. .l. Leonard and .l. V. Paukstelis, J. Org. Chem., 28, I397 (1963) when the amine is a secondary amine, to give the corresponding Schiff base or immonium salt, respectively. The product so obtained is reduced with sodium borohydride, see E. Schenker, Angew. Chem., 73, SI (l96l to yield compounds of formula I in which R, R R", R, R, R, R and X are as defined in the first instance -AlkNR"R is an amino(lower)alkyl in which Alk is Ch or AlkCH wherein Alk is as defined in the first instance and R" and R are as defined in the first instance.

Alternatively, the latter compounds of formula I may be obtained by converting the above corresponding alcohol to a reactive intermediate such as the corresponding halide, mesylate or tosylate, which may then be reacted with two or more molar equivalents or an amine of formula HNRR" in which R and R are as defined in the first instance. Preferably this reaction is performed in a suitable inert solvent, for example, tetrahydrofuran, at 40 to IC. or at the boiling point of the reaction mixture for a period of eight to 24 hours. in connection with alkylations of amines of formula HNRR* in which R is hydrogen and R" is lower alkyl as disclosed herein, it is generally more advantageous with respect to yields to perform the alkylation with the corresponding N-benzyl derivative if said amine, i.e., an amine of formula HNR"R in which R is benzyl and R is lower alkyl. Thereafter, when all appropriate transformation have been performed, the N- benzyl group may be removed by hydrogenolysis with a catalyst, preferably palladium on carbon, to give the desired compounds of formula I.

Alternatively, the above aldehyde is oxidized with a suitable oxidizing agent to yield the corresponding acid intermediates of formula V described in section (a). Although a variety of suitable oxidizing agents may be used for this purpose, for example, silver oxide, alkaline permanganate, hydrogen peroxide, the use of silver oxide according to the method of M. Delepina and P. Bennet, Compt. rend., l49,39 (I909) is preferred.

Again alternatively, the above aldehyde is converted to its oxime which on reduction with a complex metal hydride yields the corresponding primary amine of formula I in which R, R R R R, R", R and X are as defined in the first instance and AIk-I\IR"R is an amino(lower)alkyl in which Alk is CH or AIkCH- wherein Alk is as defined in the first instance and R" and R are hydrogen.

In turn these latter compounds of formula I may be further N-alkylated on the nitrogen of the primary amine with the appropriate lower alkyl halide to the corresponding compounds of formula I in which Y is AII NR"R wherein Alk is CH or AIkCH wherein Alk is as defined in the first instance and R is hydrogen or lower alkyl and R is lower alkyl (i.e. aecondary or tertiary amines). In this case depending on the particular derivative desired the N-alkylation may be effected with one or two moles of the alkyl halide to give respectively the secondary or tertiary amine. On the other hand the N-Alkylation may be effected in two steps introducing a different alkyl group each time to afford the corresponding tertiary amine in which R and R" are different lower alkyls.

When it is desired to prepare the above tertiary amine compounds in which R or R are either or both methyl, an alternative alkylation method comprises reacting the appropriate corresponding primary or secondary amine with an aqueous mixture of a substantial excess of formaldehyde and formic acid according to the conditions of the Eschweiler-Clarke reaction, see M. L. Moore, Organic Reactions, 5, 3OI I949), whereby N-methylation is effected.

Another N-alkylation method which may be applied to the above primary and secondary amines involves acylation with a lower alkanoic anhydride or acid halide and subsequent reduction of the resulting amide.

Furthermore, the above primary amines may be used to prepare corresponding compounds of formula I in which R and R together with the nitrogen atom to which they are joined form a heterocyclic amine radical as defined in the first instance. When used in this manner the primary amines are subjected to known N- alkylation methods, for example, see Method J described by R. B. Moffet, J. Org. Chem., I4, 862 I949), with the appropriate a,w-dibromides, for example, tetramethylene dibromide, pentamethylene dibromide, bis( 2-ehloroethyl )ether, bis( 2-chloroethyl )benzylamine followed by hydrogenation in the presence of 10% palladium on carbon to remove the protecting benzyl group, a bis( 2-chloroethyl) lower alkylamine or a bis( 2-chloroethyl )-N-[ hydroxy( lower )alkyllamine, to give the corresponding desired compound of formula I in which R and R" together with the nitrogen atom to which they are joined form a heterocyclic amine radical, i.e. a pyrrolidino, piperidino, morpho- Iino, piperazino, 4-(lower)alkyl-l-piperazinyl or 4- [hydroxy( Iower)alkyl]- I -piperazinyl, respectively.

d. Preparation and Conversion of Intermediates of Formula V (Z Alk l Intermediates of formula V in which Z is AIk L wherein Alk and L are as defined in the first instance, are obtained when a starting material of formula III is condensed with a [3, y or S-haIoketone of formula RCOAlk L in which R, Alk and L are as defined in the first instance in the presence of a suitable acid catalyst according to the conditions described above for the condensation (Ill IV V). The haloketones are either known, for example, 4-chIorobutan-2-one, or they may be prepared by known methods, for instance, see Roods Chemistry of Carbon Compounds", cited above, Vol. lc., pp. 71 and Methoden der Organischen Chemie, Houben-Weyl, E. Muller, Ed., Vol V/3, Georg Thieme Verlag, Stuttgart I962, pp. 5]] 1076.

Thereafter these intermediates of formula V are treated with a two molar excess of an amine of formula HNRR in which R and R are as defined in the first instance to yield the compounds of formula I in which R, R R, R, R", R", R and X are as described in the first instance, and AIkNRR is an amino(lower)alkyl in which Alk is Alk as defined in the first instance and R" and R are as defined above. Preferably this re action is performed in a suitable inert solvent, for example, tetrahydrofuran at the boiling point of the reaction mixture for a period of 8 to 24 hours.

e. Preparation and Conversion of Intermediates of Formula V (Z AIkNRCOR Intermediates of formula V in which Z is AIkNR- "COR wherein Alk, R and R are as defined in the first instance are readily obtained by the condensation (Ill IV V) by using ketoamides of formula in which R, Alk, R" and R are as defined in the first instance together with the appropriate starting material of formula III.

The ketoamides used herein are either known, for example, formamidoacetone [A, Treibe and W. Sutter, Chem. Ber., 84, 96 I I )1, see also R. H. Wiley and O. H. Borum, J. Amer. Chem. Soc., 70, 2005 (I948),

or may be prepared by known procedures, for example, see Methoden der Organischen Chemie", cited above, Vol. Xl/l 1957, especially pp. 58 62, 285 289 and 508 509, and F. F. Blicke, Organic Reactions, 1, 303 1942).

Thereafter, reduction with a complex metal hydride converts the instant intermediates of formula V to oxazinoindoles of formula l in which R, R", R", R, R", R, R", and X are as described in the first instance, and -Alk-NR"R is an amino(lower)alkyl in which Alk and R" are as defined in the first instance and R is lower alkyl.

f. Preparation and Conversion of Intermediates of Formula V (Z Alk N Intermediates of formula V in which Z is Alk-N0 wherein Alk is as defined in the first instance, are obtained by the condensation (lll IV V) when the starting materials of formula [11 and appropriate 01-, B-, 'y-, and S-nitroketones of formula in which R and Alk are as defined in the first instance are employed therein in the presence of a suitable acid catalyst. in this case trifluoroaeetic acid is the preferred acid catalyst.

The nitroketones used herein are either known, for example, l-nitro-2-propanone, N. Levy and C. W. Scaifc, J. Chem. Soc., 1 I00, 1946) and 5-nitro-2- hexanone, H. Shechter, et al., J. Amer. Chem. Soc. 74, 3664 1952) or they may be prepared by known methods, for example, see Levy and Scaife, cited above, Shecter, et al. cited above, Rodds Chemistry of Carbon Compounds, cited above, Vol. lc, pp. 71 72 and Methoden der Organischen Chemie", cited above, Vol. X/l, 1971, p. 203.

Thereafter, these intermediates of formula V are reduced with a complex metal hydride, preferably lithium aluminum hydride, to afford the oxazinoindoles of formula l in which R. R R, R, R", R, R and X are defined in the first instance, and AlkNR*R" is an amino(lower)alkyl in which Alk is defined in the first instance and R" and R are hydrogen.

If desired the latter compounds may be N-alkylated according to the methods described in section (c) to give the compounds of formula I in which R, R R, R. R, R", R and X are as defined in the first instance and AlkNR"R is an amino(lower)alkyl in which Alk, R" and R are as defined in the first instance.

The following examples illustrate further this invention.

EXAMPLE 1 3-Methylindole-l-ethanol(lll: R R", R, R and R H R =CH and X =OH) Procedure A:

Commercial n-butyl lithium in hexane (3.05 mole) is diluted with 1000 ml of dry tetrahydrofuran (THF). To this cooled (l() to 0C) solution the starting material of formula II. skatole (393 g, 3.0 mole) in l000 ml of dry THF, is added dropwise. The reaction is stirred at the same low temperature for l hour and then 300 ml of ethylene oxide in 300 ml of dry THF is added to the mixture. The temperature of the reaction is allowed to rise to room temperature and at this temperature the reaction is stirred overnight.

THF is evaporated and the residue is dissolved in methylene chloride and washed with concentrated HCl. The methylene chloride solution is then washed with 10% sodium bicarbonate, water and dried (MgSO The solvent is evaporated and the product distilled at reduced pressure to give the title compound, b.p. l24C/O.25 mm.

Procedure B:

The starting material of formula II, skatole (35 g, 0.276 mole) in 300 ml of dimethylformamide (DMF) is added dropwise to stirred mixture of sodium hydride (14.0 g, 55% oil dispension) in 325 ml of DMF. The mixture is heated at 40C for 2 hours. After cooling in an ice-water bath ethyl bromoacetate (116.5 g, 0.7 mole) is added dropwise keeping the temperature below 20C. After the addition, stirring is continued for 5 minutes, and then water added cautiously to destroy any excess hydride. The reaction mixture is partitioned between water and ether. The ether layer washed with water, dried (MgSO and evaporated under reduced pressure.

The residue, 3-methyl-indoIe-l-acetic acid ethyl ester, is dissolved in 900 ml of methanol, potassium hydroxide g) in 400 ml of 1:1 methanol-H O is then added. The mixture is stirred at room temperature for 1 /2 hours. The methanol is evaporated under reduced pressure. The residue is diluted with water (800 ml) and extracted (3X) with ether. Acidification with 6NHCI of the aqueous phase yields 3-methyl-indolel acetic acid, m.p. l74l76C.

The latter compound (47.5 g., 0.25 mole) in 1000 m1 of ether is slowly added to a stirred mixture of lithium aluminum hydride (12.5 g) (0.32 moles) in 700 ml of ether. The reaction is kept below 15C using an icewatcr bath. The reaction is stirred for 15 minutes after the addition, the excess hydride destroyed with water, and the precipitate collected. The ether filtrate is washed with water, dried over sodium sulfate and evaporated under reduced pressure to afford an oil. Chromatography on silica gel using 15% ethylacetate in benzene as eluant gives the title compound, identical with the product of procedure A.

By following the procedure A of Example 1 other in dolel-ethanol intermediates of formula III for example those listed in Examples 6 to 55, may be prepared by the appropriate choice of the starting material of formula ll and ethylene oxide derivative. For example, by replacing skatole and ethylene oxide with equivalent amounts of 3,7-dimethyl-indole, R. Robinson et al., cited above, and 3,3-dimethyl-l,2-epoxybutane, V. Franzen and H. E. Driesen, cited above, respectively, a mixture of B-isopropyl-a,3,7-trimethyl-indole-lethanol and a-isopropyl-B,3,7-trimethyl-indole-lethanol, are obtained. Such mixtures of positional isomers may be separated by fractional distillation, fractional recrystallization or chromatography. Likewise, the replacement of skatole with 3-isopropylindole, R. Robinson et al. cited above, in procedure A of Example 1 yields 3-isopropylindole- 1 -ethanol.

By following procedure B of Example 1 other indolel-ethanol intermediates of formula [II in which R and R are hydrogen may be prepared by the appropriate choice of the starting material of formula II and a-haloacetic acid lower alkyl ester of formula LCR R COO-(lower alkyl) in which L is halo and R and R are hydrogen or lower alkyl. For example, by replacing skatole and ethyl bromoacetate with equivalent amounts of 3-ethylindole, R. Robinson et al., cited above, and 2,3-epoxybutane, F. G. Bordwell and P. S. Landis, J. Amer. Chem. Soc., 79, 1593 (1957), respec tively, a,B-dimethyl-3-ethyl-indole-l-ethanol is obtained. Likewise the replacement of skatole with 3- butylindole, R. Robinson et al., cited above, in the procedure B of Example 1 yields 3-butylindole-l-ethanol.

EXAMPLE 2 3Methylindole-l-ethanethiol (lll: H R, R, R and R H, R CH and X SH) Procedure A:

N.N-dicyclohexylcarbodiimide (9.0 g) is added to a cooled, stirred solution of 3-methylindole-l-ethanol (3.0 g) in 30 ml of dimethyl sulfoxidebenzene (2:1) containing trifluoroacetic acid (0.6 ml) and pyridine 1.12 ml). The reaction is stirred at room temperature under nitrogen for 5 hours. The reaction mixture is now diluted with 300 ml of ether, followed by the dropwise addition of a solution of oxalic acid (3.78 g) in l l ml of methanol. After 30 minutes, water (300 ml) is added and the insoluble material is collected. The organic phase is washed with water (2X), 5% aqueous sodium bicarbonate (2X) and water (2X). After drying (MgSO the organic phase is evaporated to yield 3- methylindole-l-acetaldehyde. The latter compound is then converted to its corresponding gem-dithiol with hydrogen sulfide and reduced with lithium aluminium hydride according to the method of T. L. Cairns et al., J. Amer. Chem. Soc., 74, 3982 1952), to yield the title compound, vmM 2570 cm".

Procedure B:

To a stirred solution of 7.2 g of 3-methylindole-lethanol, described in Example 1, in 500 ml. of dry ether (ice bath) is slowly added 1.2 ml of phosphorus tribromide in 100 ml of dry ether. A dark red oily complex separates. The reaction mixture is stirred 36-48 hours at room temperature, then decomposed with ice and water. The separated ether-layer is quickly washed with a 10% solution of sodium bicarbonate and with water again, dried over calcium chloride for 2 min., decanted, and dried over magnesium sulfate for 30 min. The filtrate is evaporated yielding l-( 2-bromoethyl)-3- methylindole.

A solution of 10.4 g. of sodium thiosulfate in 60 ml. of water and 100 ml. of ethanol is poured onto 8.6 g. of l-( 2-bromoethyl )-3-methylindole. The reaction mixture is stirred and heated at reflux for 3.5 hr., allowed to cool, and evaporated to dryness. The solid residue is dissolved in boiling ispropanol, dried with a hydrated alkali-aluminum silicate (Molecular Sieves), and filtered. Chilling of the filtrate causes 6.4 g. ofthe sodium indolyethyl thiosulfate derivative to precipitate. This material is collected by filtration and washed with ether. The isolated intermediate is heated at reflux with a solution of sodium hydroxide (9 g. of NaOH, 60 ml. of water, 140 m1. of ethanol) for 3 hr. Ethanol is removed under reduced pressure, the aqueous residue diluted with water and extracted with three portions of ether. Combined ether extracts are washed with water, saturated brine solution, and dried over magnesium sulfate. The filtrate is evaporated, to yield bis-[2-( 3- methylindolel -yl )ethyl ]disulfide.

The latter product 1.4 g.) in 100 ml. of dry ether is dropped into a stirred suspension of 600 mg. LiAlH, in

m1. of dry ether. The reaction mixture is heated to reflux for 3 hr. and then kept for 15 hr. at room temperature. Decomposition with 2.8 ml. of water is carried out in a stream of nitrogen. After 60 min. of stirring, a white precipitate is filtered off with suction, the cake was washed with ether, and the filtrate dried over magnesium sulfate. The clear ether solution is evaporated to give the title compound.

By following procedure A or B of Example 2 other indole-l-ethanethiol intermediates of formula [I], for example those described in Examples 57 to 106 may be prepared by the appropriate choice of indole- 1 -ethanol intermediates of formula III. For example, by replacing 3-methylindole-lethanol with an equivalent amount of B-isopropyl-a,3,7-trimethylindole- 1 -ethanol, B-isopropyl-a,3,7-trimethyl-indole-l-ethanethiol is obtained. Likewise, by replacing 3-methylindole-l-ethanol with an equivalent amount of 3-isopropylindole-l-ethanol, 3-isopropylindole- 1 -ethanethiol is obtained.

EXAMPLE 3 3,4-Dihydro-1,lO-dimethyl-lH-l ,4-oxazino[4,3-a]indole-l-acetic acid (V; R and R CH R R", R, R and R H, X O and Z CH COOH).

A mixture of the intermediate of formula 1]], 3- methylindole-l-ethanol(26.5 g., 0.15 mole), described in Example 1, in toluene (600 ml.), ethyl acetoacetate (36 g., 0.20 mole) and p-toluenesulfonic acid (2.0 g.) is heated at reflux for 6 hr. using a water separator. The toluene solution is washed with water, 5% bicarbonate solution, and again with water. The solution is then dried over sodium sulfate and the solvent evaporated under reduced pressure to give an oil. The oil was subjected to chromatography on silica gel. Elution with 10% ethyl acetate in benzene and concentration of the eluate affords the ester, 3,4-dihydro-l ,lO-dimethyll H- l,4-oxazino[4,3-a]indole-l-acetic acid ethyl ester, as an oil, v,,,,,,""l725 cm.

Hydrolysis of this ester to the title compound is effected as follows: The ester (39.9 g.) is dissolved in 800 ml. of methanol containing 22.5 g. of KOH in 20 ml. of water. After stirring for 5 hr. at 50C. and for 12 hr. at room temperature, the solvent is evaporated under reduced pressure. The residue is taken into water and washed twice with ether, acidified with 6N HC1 and extracted with ether. The ether solution is washed once with water, dried (Na SO and evaporated under reduced pressure to afford a solid. The solid is recrystallized from petroleum ether to afford the title compound, m.p. l38 139C, nar (CDCl 51.75 (s, 3H), 2.86 and 3.18 (d, J 14.5 cps, 2H), 4.07 (m, 4H).

An equivalent amount of methyl acetoacetate may replace ethyl acetoacetate in the procedure of this Example. In this case, 3,4-dihydro-1,lO-dimethyl-lH-IA- oxazino[4,3-a]-indole-l-acetic acid methyl ester is obtained as the ester.

An equivalent amount of propyl acetoacetate may replace ethyl acetoacetate in the procedure of this Example. In this case. 3,4-dihydro-l,l0-dimethyl-lH-l,4- oxazino[4,3-a]-indole-l-acetic acid propyl ester is obtained as the ester.

EXAMPLE 4 l l-Dimethyl-3.4-dihydro l H- l ,4-oxazino[4,3- alindolel -propionic acid (V; R and R =CH;,, R R", R. R and R H, X O and Z CH CH COOH) Procedure A:

A mixture of the intermediate of formula III, 3- methylindole-l-ethanol (29.7 g., 0.17 mole), described in Example 1, ethyl levulinate (26.96 g., 0.]87 mole) and p-toluenesulfonic acid (2.25 g.) in dry benzene (650 ml.) is refluxed with stirring for 12 hr. with hydrated akalialuminum silicate (Molecular Sieves No. 4). The benzene solution is washed with 5% aqueous NaHCO followed by water. Concentrations of the solution gave a residue, which is passed through a silica gel column using l5% ethyl acetate in benzene to afford the ester, 3,4-dihydro-l ,l0-climethyl-lH-l ,4- oxazino[4,3-a]indole-l-propionic acid ethyl ester, as on oil, v I730 cm.

This ester (41.9 g.) is dissolved in 650 ml. of methanol containing 23 g. of KOH in 50 ml. of water and heated at 50C. for l hr. The solvent is evaporated and the residue taken into water. The aqueous mixture is washed with ether twice, acidified with 6N HCl and extracted three times with ether. The ether solution is washed once with water, dried over MgSO and evapo rated, under reduced pressure to yield a solid. The solid is recrystallized from ethyl acetate-petroleum ether to mg), 75 ml. of benrene, 1.7 g. of phosphorus pentoxide and about 0.5 g. of diatomaceous earth (Celitc) is stirred magnetically at room temperature for IS min. and then at 70C. for l /2 hr. The reaction mixture is filtered. The filtrate is washed three times with 5N NaOH; the combined aqueous phase is washed twice with ether and then rendered acidic with cold 50% HCl. The aqueous phase is extracted with chloroform. The chloroform extract is dried (Na SO and evaporated to dryness. Recrystallization of residue from ethyl acetate-petroleum ether affords the title compound, identical to the product of procedure A of this Example.

The procedure of Example 3 and 4 (Procedure A) may be followed to prepare other intermediates of formula V in which R, R R, R, R R, R, X are defined in the first instance and Z is COOR or AlkCOOR'" wherein R'" and Alk' are as defined in the first instance. Examples of such compounds are listed in Tables I and ll. In each of these instances intermediate of formula [I] and ketoester listed therein are used in an equivalent amount to the intermediate of formula III and ketoesters listed in Examples 3 and 4 (Proce dure A). Note that in each of these instances an ester is obtained prior to hydrolysis. This ester is the corresponding intermediate of formula V in which Z is COOR' or Alk-COOR"" wherein R is lower alkyl and Alk' is defined in the first instance, the alkyl portion of said ester being derived from the R' portion of give the title compound, m.p. ll5 ll6C., nmr the ketoester of formula IV employed therein. (CDCl 5| .62 (s, 3H), 2.30 (m, 7H), 4.04 (4H), 7.2l Likewise, the procedure ofExample 4 (Procedure B) 7.52 (m, 4H), l0.93 l H). may be used to prepare the products listed in Tables 1 Procedure B: and II except that in this case an equivalent amount of A mixture of the intermediate of formula ll], 5- the corresponding ketoacid of formula IV is used inmethylindole-l-ethanol (500 mg), levulinic acid (580 stead f th k e t li d i h t bl TABLE I PRODUCT: (PREFIX KETOESTER OF LISTED BELOW FORMULA IV, 3,4-DlHYDRO-lH-l INTERMEDIATE OF 4-OXAZlNO[4,3-al lNDOLE-l(SUFFlX EX. FORMULA lll IN WHlCH X IS OH RC-Alk'CO-OR'" LISTED BELOW) R R R R R R R Alk'C0 R'" PREFIX/[SUFFIX S H H H H H CH; CH CO C H l, lO-dimethyll/carhoxylic acid (1 CH H H H CH, C H Co C,H, l-ethyl-3,lU-dimethyll- /Carboxylic acid 7 n ('.,H, H H 5 CH, CH, n C,H, Co CH, l,3diisopropyl-8,ltl-

dimethyl/lcarhoxylir: acid 8 CH:, CH,, H H 5-OH CH CH CO CH lS-hydroxyl ,3] l (ltetramethyl/Icarhoxylic acid 9 H H H H 7C.;H (1H,, nC;,H CO CH;, 6,]0-diethyl-lpropyll/earboxylic acid H] H H i--C,,H; H H iC,,H D CO CH, l-cyelopropyl-4,IU-diisopropyl/learboxylic acid I l CH CH H C H, H C- H; CO CH l-cyclopentyl-4,4 l()- triethyl-3 3-Llimcthyl/- /carboxylic acid l2 CH, CH, CH; (H C'O C- ,H l,4, lll-trimethyll/aectic acid I} H H H CH C H CH CO (2H3 l-ethyl-l(lmcthyl//aeetic acid 14 H H H H CH nC;,H,- CH CO C H lU-melhyl-lpropyll/acetic acid, m. '1.l46 [48C. l5 H H H H CH, i C,H CH,Co H Lisopropyl-IU- methyl/Iacctic acid In (H:, H H H CH nC;,H CH CO H, 3.l l-dimcth)l-lpropylf/aeetic acid l7 CH, H (,H, (H;, H (H C.,H,, (H CO (1H,, l,4-diethyl-3.l0-dimcthyl laeetie acid IX H H H H H CH CH CH(CH;,)CO C H a l lll-trimelhyl/iacctic acid EXAMPLE 107 Tricthylemine (6 g.) and then ethyl chloroformatc g.) are added to a cooled solution (-5C.) of l,lO- dimethyl-3,4-dihydrol H-l ,4-oxazino[4,3-a]indolel acetic acid l0 g. described in Example 3, in 150 ml. of tetrahydrofuran (THF). After being stirred for 2 hr. at l0C. the suspension is further cooled to ca. l0C. and treated with methylamine (66 ml. of the 40% water solution) and stirred at given temperature for an additional hour. Most of the THF is evaporated and the res idue partitioned between ether and water. The ether solution is washed with water, dried (MgSO and concentrated to afford a solid. The solid is recrystallized from ethyl acetate to afford the title compound, m.p.

l3l 133C.

In the same manner but replacing the 40% aqueous solution of methylamine with an equivalent amount of the amines of formula HNR"R". ammonium hydroxide (concentrated), dimethylamine (30% aqueous solution), n-hexylamine aqueous solution), diethylamine aqueous solution), isopropylamine (7:

aqueous solution ethylamine (70% aqueous solution), pyrrolidine aqueous solution), piperidine, morpholine, N-methylpiperazine,

l, l 0-dimethyl-3,4-dihydrol H-l ,4-oxazino[4,3-a]indole-l-acetamide, m.p. l56 l57C., nmr (CDCI;,) SL6) (3H), 2.33 (3H),

N,N, l l O-tetramethyl-3,4-dihydrol H-l ,4-

oxazino[4,3-a]indole-l-acetamide. nmr (CDCl 51.78 (3H). 2.33 (3H), 2.95 (6H),

l, l 0-dimethyl-N-hexyl-3,4-dihydro l H- l ,4- oxazino[4,3-a]indolel -acetamide,

N,N-diethyl-l l O-dimethyl-3,4-dihydrol H- l ,4-

oxazino[4,3a]-indolel -aeetamide.

l, l O-dimethyl-N-isopropyl-3,4-dihydrol H-1 ,4- oxazino[4.3-a]indolel -acetamide,

l, l O-dimethyl-N-ethyl-3 ,4-dihydr0- l H-1 ,4- oxazino[4,3-a]indole-l-acetamide, m.p. 1 14 1 16C., l-[( l ,l0-dimethyl-3,4-dihydro-1 H- l ,4-oxaZino-[4,3- alindoll -yl )-acetyl ]-pyrrolidine,

l-[( l l0-dimethyl-3 ,4-dihydrol H- l ,4-oxazinol 4,3- a]ind0ll -yl )-aeetyl ]piperidine,

4-[( l l0-dimethyl-3 ,4-dihydrol H- l ,4-oxazino[ 4.3- a]ind0ll -yl )-acetyl ]morpholine, and

l-methyl-4-[( l.l()-dimethyl-3,4-dihydrol H l .4- oxazino[4,3-a]indol-l-yl)aeetyllpiperazine, are obtained respectively.

By following the procedure of Example 107 but using as starting material an equivalent amount of one of the acid compounds of formula V. described in Examples [4 to l06, instead of 3,4-dihydro-l l0-dimethyl-3,4- dihydrol H-] ,4-oxazino[4,3-a]indolel -acetic acid, and using an equivalent amount of an appropriate amine such as ammonia or a primary or secondary amine described in Example I07, then the corresponding amide compound of formula V is obtained. Examples of such amides are listed as products in Tables lll, IV, V and VI together with the appropriate starting material and amine used for the preparation of the amide. ln each case the starting material is noted by the example in which it is prepared.

dition salt (hydrohromide) has m.p. 191 193C. after recrystallization from isopropanol-ether, 1,10- dimethyll -[2-( isopropylamino )ethyl ]-3,4-dihydro- 1 H-l ,4-oxazino[4,3-a indolc.

1 .lO-dimethyl-1-[2-(ethylamino)ethyl]-3,4-dihydrolH-l,4-oxazino[4,3-alindole, nmr (CD 81.58 (3H). 2.32 (3H), corresponding hydrobromic acid addition salt has m.p. 196 198C, after recrystallization from isopropanol-ether,

1,10-dimethyl- I 2-( l-pyrrolidinyl )ethyl ]-3,4-dihydrolH-l.4-oxazino[4.3-a]indolc, nmr (CDCl;,) 81.60 (3H 2.30 (3H corresonding hydrochloric acid addition salt has m.p. 223 225C, after recrystallization from isopropanol-ether, 1,l0-dimethyl-1-(2-piperidinoethyl)-3,4-dihydro-1H- 1,4-oxazinol4,3-a]indole, nmr (CDCl 81.61 (3H), 2.33 (3H), corresponding hydrobromic acid addition salt has m.pv 253 255C, after recrystallization from methanol, 1,IO-dimethyl-1-(2-morpholinoethy1)-3,4-dihydro-l H 1H-l,4-oxazino[4,3-a]indole-l-acetamide,

l,4-oxazino[4,3-]indolc, nmr (CDC1 51.60 (3H), 2.31 (3H), corresponding hydrochloric acid addition salt has m.p. 234 236C, after recrystallization from isopropanol-ether, and l,IO-dimethyl-1-[2-(4-methyl-1-piperazinyl)ethyl]- 3,4-dihydro-lH-1,4-oxazino[4,3-a]indole, nmr (CDC1 61.62 (s, 3H), 2.32 (s, 3H) corresponding maleic acid addition salt (dimaleate) has m.p. 196 198C, after recrystallization from methanol, respectively.

By following the procedure of Example 284 but using as starting material an equivalent amount of one of the amide compounds of formula V, described in Examples 108 to 283 instead of N,l.10-trimethyl-3,4-dihydrothen the corresponding compounds of formula 1 are obtained. Examples of such compounds of fonnula 1 are listed as products in Tables V11 and V111 together with the appropriate starting material. In each case the starting material is noted by the example in which it is prepared.

TABLE V" EXAMPLE NO. OF EXAMPLE IN WHICH PRODUCT: (PREFIX LlSTED BELOW)- PREPARED INDOLE 108 1,10-dimethyll-[3-(methylamino)- propyl], nmr (CDCI 61.62 (3H) 2.32 (3H), corresponding hydrochloric acid addition salt has mp. 193 195C, after rccrysta| lization from isopropanol ether 10) l( 3aminopropyl 1-1 IU-dimethyl,

nmrlCDCln) 61.58 (3H1, 1.90 (2H). corresponding hydrochloric acid addition salt has mp. 204 206C, after recrystallization from methanol-ether 1, l0-dimethyl-l-[3-(dimethylamino) propyll, nmr (CDCI,, 51.64 (3H), 2.33 (3H). 2.35 (4H). corresponding hydrochloric acid addition salt has m.p. 200- 201C. after recrystallization from methanol-ether l 1 l l,IO-dimethyl-1-[3 (cthylamino]- propyl]. nmr(CDCl 81.61 (3H), 2.33 (3H), corresponding, hydrochloric acid addition salt has m.p. 220 222C, after recrystallization from ethanol-ether 1 12 1-1 3-dicthylamino1pr0pyl |-1,10

dimcthyl, nmr (CDCI 60.94 (t, 6H

1.58 (s, 3H), corresponding hydrobromic acid addition salt has mp. 174 176C, after recrystallization from isopropanol 1 l3 1,10-dimethyll [(methy1amino)mcthy| I 1 l4 l-(aminomethyl)-1,10-dimethyl 1 l5 l-[(dimcthylamimnmethyl H-ethyl- 1,3,10-trimcthyl 1 l6 1.3-diisopropy1-8.IU-dimethyl-lll hcxylamino)methy1 1 l7 l-(clhylaminojmcthyl-l-hydroxy- 1,3,3. 1 U-tctramcthyl 1 18 6,10-dicthy1-1-(mcthy1amino)mcthy1- l-propyl l 19 lcyclopropyl-1-(dimcthylamino)- mcthy1-4,10isopropyl I20 l-cycIopcntyl-3,3-dimethyl- I [dimethylamino)mcthyl-4,4,10-triethyl I21 1-1mcthylaminojcthyl-l,4,l0-trimcthyl 122 l-( Z-aminocthyl)-1cthyl- Ill-methyl 123 1-1Z-(dimcthylaminoJethylll-cthyL l0 mcthyl 124 l-cthyl l 2-( hcxylamino )cthyH- 11)- methyl 125 l-(2-(diethylaminmcthyl|-1-cthyl-l0- methyl 126 l(1-methy1-l 124mcthylamino1cthylI l-propyl 127 l -(aminocthy1]- l0-mcthyll-propyl 

1. A PROCESS FOR PREPARING A COMPOUND OF FORMULA I
 2. The process of claim 1 in which the compound of formula I is reacted with a pharmaceutically acceptable acid to give the corresponding acid addition salt.
 3. The process of claim 1 in which R1 is methyl, R2, R3, R4, R5 and R6 are hydrogen, R7 is methyl, X is oxy, R8 is hydrogen, R9 is methyl, Alk3 is CH2CH2, X1 is hydroxy and Z is CH2CH2l.
 4. The process of claim 1 in which R1 is methyl, R2, R3, R4, R5 and R6 are hydrogen, R7 is methyl, X is oxy, R8 is hydrogen, R9 is hydrogen, Alk3 is CH2CH2, X1 is hydroxy and Z is CH2CH2l.
 5. The process of claim 1 in which R1 is methyl, R2, R3, R4, R5 and R6 are hydrogen, R7 is methyl, X is oxy, R8 is methyl, R9 is methyl, Alk3 is CH2CH2, X1 is hydroxy and Z is CH2CH2l.
 6. The process of claim 1 in which R1 is methyl, R2, R3, R4, R5 and R6 are hydrogen, R7 is methyl, X is oxy, R8 is ethyl, R9 is ethyl, Alk3 is CH2CH2, X1 is hydroxy and Z is CH2CH2l.
 7. The process of claim 1 in which R1 is methyl, R2, R3, R4, R5 and R6 are hydrogen, R7 is methyl, X is oxy, R8 is hydrogen, R9 is ethyl, Alk3 is CH2CH2, X1 is hydroxy and Z is CH2CH2l.
 8. The process of claim 1 in which R1 is methyl, R2, R3, R4, R5 and R6 are hydrogen, R7 is methyl, X is oxy, R8 and R9 together with the nitrogen atom to which they are joined form a 1-pyrrolidinyl, Alk3 is CH2CH2, X1 is hydroxy and Z is CH2CH2l.
 9. The process of claim 1 in which R1 is methyl, R2, R3, R4, R5 and R6 are hydrogen, R7 is methyl, X is oxy, R8 and R9 together with the nitrogen atom to which they are joined form a piperidino, Alk3 is CH2CH2, X1 is hydroxy and Z is CH2CH2l.
 10. The process of claim 1 in which R1 is methyl, R2, R3, R4, R5 and R6 are hydrogen, R7 is methyl, X is oxy, R8 and R9 together with the nitrogen atom to which they are joined form a morpholino, Alk3 is CH2CH2, X1 is hydroxy and Z is CH2CH2l.
 11. The process of claim 1 in which R1 is methyl, R2, R3, R4, R5 and R6 are hydrogen, R7 is methyl, X is oxy, R8 and R9 together with the nitrogen atom to which they are joined form a 4-(methyl)-1-piperazinyl, Alk3 is CH2CH2, X1 is hydroxy and Z is CH2CH2l.
 12. The process of claim 1 in which R1 is methyl, R2, R3, R4, R5 and R6 are hydrogen, R7 is methyl, X is oxy, R8 is hydrogen, R9 is methyl, Alk3 is CH2CH2CH2, X1 is hydroxy and Z is CH2CH2CH2l.
 13. The process of claim 1 in which R1 is methyl, R2, R3, R4, R5 and R6 are hydrogen, R7 is methyl, X is oxy, R8 is hydrogen, R9 is hydrogen, Alk3 is CH2CH2CH2, X1 is hydroxy and Z is CH2CH2CH2l.
 14. The process of claim 1 in which R1 is methyl, R2, R3, R4, R5 and R6 are hydrogen, R7 is methyl, X is oxy, R8 is methyl, R9 is methyl, Alk3 is CH2CH2CH2, X1 is hydroxy and Z is CH2CH2CH2l.
 15. The process of claim 1 in which R1 is methyl, R2, R3, R4, R5 and R6 are hydrogen, R7 is methyl, X is oxy, R8 is hydrogen, R9 is ethyl, Alk3 is CH2CH2CH2, X1 is hydroxy and Z is CH2CH2CH2l.
 16. The process of claim 1 in which R1 is methyl, R2, R3, R4, R5 anD R6 are hydrogen, R7 is methyl, X is oxy, R8 is ethyl, R9 is ethyl, Alk3 is CH2CH2CH2, X1 is hydroxy and Z is CH2CH2CH2l.
 17. The process of claim 1 in which R1 is propyl, R2, R3, R4, R5 and R6 are hydrogen, R7 is methyl, X is oxy, R8 is methyl, R9 is methyl, Alk3 is CH2CH2, X1 is hydroxy and Z is CH2CH2 l.
 18. The process of claim 1 in which R1 is propyl, R2, R3, R4, R5 and R6 are hydrogen, R7 is methyl, X is oxy, R8 is ethyl, R9 is ethyl, Alk3 is CH2CH2, X1 is hydroxy and Z is CH2CH2 l.
 19. The process of claim 1 in which R1 is methyl, R2, R3, R4, R5 and R6 are hydrogen, R7 is methyl, X is oxy, R8 and R9 together with the nitrogen atom to which they are joined form a 1-pyrrolidinyl, Alk3 is CH2CH2CH2, X1 is hydroxy and Z is CH2CH2CH2 l.
 20. The process of claim 1 in which R1 is methyl, R2, R3, R4, R5 and R6 are hydrogen, R7 is methyl, X is oxy, R8 and R9 together with the nitrogen atom to which they are joined form a piperidino, Alk3 is CH2CH2CH2, X1 is hydroxy and Z is CH2CH2CH2l. 